<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>javascript 函数</title>
	<script type="text/javascript">
		
		function aa(){
			alert('hello!');			
		}



	</script>
</head>
<body>
	<input type="button" name="" value="弹框" onclick="aa()">
</body>
</html>